JOHANNESBURG — The suspicious death of Rwanda’s former spy chief in a plush Johannesburg hotel is resurrecting allegations that Western-backed President Paul Kagame is orchestrating a campaign to kill opponents at home and abroad.

South African police opened a murder investigation after former Col. Patrick Karegeya’s body was discovered on New Year’s Day.

JOHANNESBURG — Scientists say a disease destroying entire crops of cassava has spread out of East Africa into the heart of the continent, is attacking plants as far south as Angola and now threatens to move west into Nigeria, the world’s biggest producer of the potato-like root that helps feed 500 million Africans.

JOHANNESBURG — About 270 miners were charged Thursday with the murders of 34 striking colleagues who were shot by South African police officers, authorities said, a development that could further infuriate South Africans already shocked and angered by the police action.

The decision to charge the miners comes under an arcane Roman-Dutch common purpose law, and it suggests President Jacob Zuma’s government wants to shift blame for the killings from police to the striking miners.

JOHANNESBURG — It’s been a disastrous year for elephants, perhaps the worst since ivory sales were banned in 1989 to save the world’s largest land animals from extinction, the wildlife trade monitoring network TRAFFIC said Thursday.

A record number of large seizures of elephant tusks represents at least 2,500 dead animals and shows that organized crime — in particular Asian syndicates — is increasingly involved in the illegal ivory trade and the poaching that feeds it, the group said.